U.S. patent application number 10/803085 was filed with the patent office on 2004-11-18 for motor vehicle lock.
This patent application is currently assigned to Brose Schliessysteme GmbH & Co. KG. Invention is credited to Kachouh, Checrallah.
Application Number | 20040227358 10/803085 |
Document ID | / |
Family ID | 32797981 |
Filed Date | 2004-11-18 |
United States Patent
Application |
20040227358 |
Kind Code |
A1 |
Kachouh, Checrallah |
November 18, 2004 |
Motor vehicle lock
Abstract
The invention relates to a motor vehicle lock with a latch and a
ratchet arrangement. The latch is able to swivel around a
swivelling axis, and be moved into an open position, a main locked
position and optionally a preliminary locked position. The ratchet
arrangement is able to be moved into at least one holding position
and into a release position. The ratchet arrangement when in the
holding position, keeps the latch, in any case, in the main locked
position. The ratchet arrangement includes ratchet kinematics and
an adjustable blocking element. By resetting the latch out of the
main locked position in the direction of the open position the
ratchet kinematics is moved and when the ratchet arrangement is in
the holding position the blocking element blocks the movement of
the ratchet kinematics which can be caused by the latch and thus
blocks the resetting of the latch.
Inventors: |
Kachouh, Checrallah;
(Dortmund, DE) |
Correspondence
Address: |
NIXON PEABODY, LLP
401 9TH STREET, NW
SUITE 900
WASHINGTON
DC
20004-2128
US
|
Assignee: |
Brose Schliessysteme GmbH & Co.
KG
Wuppertal
DE
|
Family ID: |
32797981 |
Appl. No.: |
10/803085 |
Filed: |
March 18, 2004 |
Current U.S.
Class: |
292/216 |
Current CPC
Class: |
E05B 85/26 20130101;
Y10T 292/1082 20150401; E05B 81/14 20130101; Y10T 292/1047
20150401; Y10S 292/23 20130101; E05B 77/02 20130101; E05B 81/20
20130101 |
Class at
Publication: |
292/216 |
International
Class: |
E05C 009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 20, 2003 |
DE |
103 12 304.0 |
Claims
What is claimed is:
1. Motor vehicle lock comprising: a latch that is swivelable around
a swivelling axis and moveable into an open position and at least
into a main locked position; and a ratchet arrangement movable into
at least one holding position and into a release position, and the
ratchet arrangement keeping the latch in the main locked position
when in the at least one holding position, the ratchet arrangement
further including, ratchet kinematics, wherein the ratchet
kinematics is moved by resetting the latch out of the main locked
position in the direction of the open position; and an adjustable
blocking element that blocks movement of the ratchet kinematics
when the ratchet arrangement is in the at least one holding
position, thereby blocking the resetting of the latch.
2. Motor vehicle lock as claimed in claim 1, wherein the ratchet
kinematics further comprises: step-down gearing, wherein a blocking
force applied by the blocking element to block the latch is reduced
by the step-down gearing.
3. Motor vehicle lock as claimed in claim 2, wherein, when the
latch is in the main locked position, a degree of reduction of the
ratchet kinematics is higher than when the latch is in a
preliminary locked position.
4. Motor vehicle lock as claimed in claim 1, wherein the motor
vehicle lock has a motorized opening drive and wherein the release
of the latch can be triggered by a motor.
5. Motor vehicle lock as claimed in claim 4, wherein the motorized
opening drive is an electric motor.
6. Motor vehicle lock as claimed in claim 1, wherein the ratchet
kinematics further comprises: a transmission lever that is
swivelable around a second swivelling axis, wherein by swivelling
the latch out of the main locked position in the direction of the
open position, the transmission lever can be moved and, when the
ratchet arrangement is in the at least one holding position, the
blocking element blocks the transmission lever.
7. Motor vehicle lock as claimed in claim 6, wherein the
transmission lever is coupled to the latch.
8. Motor vehicle lock as claimed in claim 7, wherein an
intermediate lever couples the transmission lever and the latch
and, wherein the intermediate lever is pivotally coupled to the
latch and to the transmission lever and, is coupled eccentrically
with regard to the respective swivelling axis of the latch.
9. Motor vehicle lock as claimed in claim 8, wherein when the latch
is in the main locked position the force acting on the transmission
lever from the latch via the intermediate lever causes torque on
the transmission lever with respect to its swivelling axis and
wherein the blocking force of the blocking element opposes the
torque on the transmission lever.
10. Motor vehicle lock as claimed in claim 2, wherein the ratchet
kinematics further comprises: a transmission lever that is
swivelable around a second swivelling axis, wherein by swivelling
the latch out of the main locked position in the direction of the
open position the transmission lever can be moved and, when the
ratchet arrangement is in the at least one holding position the
blocking element blocks the transmission lever.
11. Motor vehicle lock as claimed in claim 10, wherein the
transmission lever is coupled to the latch.
12. Motor vehicle lock as claimed in claim 11, wherein an
intermediate lever couples the transmission lever and the latch and
wherein the intermediate lever is pivotally coupled to the latch
and to the transmission lever and, is coupled eccentrically with
regard to the respective swivelling axis of the latch.
13. Motor vehicle lock as claimed in claim 12, wherein when the
latch is in the main locked position, the force acting on the
transmission lever from the latch via the intermediate lever causes
torque on the transmission lever with respect to its swivelling
axis, and wherein the blocking force of the blocking element
opposes the torque.
14. Motor vehicle lock as claimed in claim 6, wherein the
transmission lever is pretensioned and wherein the blocking force
of the blocking element opposes the pretensioning of the
transmission lever.
15. Motor vehicle lock as claimed in claim 10, wherein the
transmission lever is pretensioned and wherein the blocking force
of the blocking element opposes the pretensioning of the
transmission lever.
16. Motor vehicle lock as claimed in claim 6, wherein the
transmission lever further comprises: at least one main catch,
wherein the blocking element can be moved to engage the
transmission lever by blocking at least via the main catch.
17. Motor vehicle lock as claimed in claim 10, wherein the
transmission lever further comprises: at least one main catch,
wherein the blocking element can be moved to engage the
transmission lever by blocking at least via the main catch.
18. Motor vehicle lock as claimed in claim 6, wherein the blocking
element is swivelable around a third swivelling axis and when the
ratchet arrangement is in the holding position, the blocking
element engages and blocks the transmission lever.
19. Motor vehicle lock as claimed in claim 10, wherein the blocking
element is swivelable around a third swivelling axis and when the
ratchet arrangement is in the holding position the blocking element
engages and blocks the transmission lever.
20. Motor vehicle lock as claimed in claim 7, further comprising:
an auxiliary locking drive, wherein the auxiliary locking drive is
coupled to the transmission lever and wherein the latch can be
moved into the main locked position by the auxiliary locking drive
via the transmission lever.
21. Motor vehicle lock as claimed in claim 11, further comprising:
an auxiliary locking drive, wherein the auxiliary locking drive is
coupled to the transmission lever and wherein the latch can be
moved into the main locked position by the auxiliary locking drive
via the transmission lever.
22. Motor vehicle lock as claimed in claim 8, wherein the coupling
of the intermediate lever to the latch includes a trip-free
mechanism and wherein movement of the latch out of the main locked
position into an overstroke position, on the other side of the main
locked position viewed from the open position, is possible without
moving the transmission lever.
23. Motor vehicle lock as claimed in claim 12, wherein the coupling
of the intermediate lever to the latch includes a trip-free
mechanism and wherein movement of the latch out of the main locked
position into an overstroke position on the other side of the main
locked position viewed from the open position, is possible without
moving the transmission lever.
24. Motor vehicle lock as claimed in claim 22, wherein the
intermediate lever is pretensioned against the latch such that the
latch can be moved into the overstroke position against the
pretensioning.
25. Motor vehicle lock as claimed in claim 23, wherein the
intermediate lever is pretensioned against the latch such that the
latch can be moved into the overstroke position against the
pretensioning.
26. Motor vehicle lock as claimed in claim 1, further comprising:
an inlet slot and wherein the blocking element, for protection
against theft, is located in the motor vehicle lock such that the
blocking element cannot be reached from of the inlet slot.
27. Motor vehicle lock as claimed in claim 11, further comprising:
a motorized opening drive, wherein the release of the latch can be
triggered by a motor.
28. Motor vehicle lock as claimed in claim 27, wherein the
motorized opening drive is an electric motor.
29. Motor vehicle lock as claimed in claim 13, further comprising:
a motorized opening drive, wherein the release of the latch can be
triggered by a motor.
30. Motor vehicle lock as claimed in claim 29, wherein the
motorized opening drive is an electric motor.
31. Motor vehicle lock as claimed in claim 23, further comprising:
a motorized opening drive, wherein the release of the latch can be
triggered by a motor.
32. Motor vehicle lock as claimed in claim 31, wherein the
motorized opening drive is an electric motor.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a motor vehicle lock with a latch
and a ratchet arrangement.
[0003] 2. Description of Related Art
[0004] Current motor vehicle locks are generally equipped with a
latch and a ratchet, in order to accomplish a non-positive
connection to a striker which is located on the motor vehicle body
as shown in EP 0 589 158 A1. The latch can be swivelled around a
swivelling axis and, in any case, can be moved into a main locked
position. The ratchet is hook-shaped and keeps the latch in the
main locked position by fitting into a corresponding shape, i.e., a
main catch on the latch. The basic concept is also used in motor
vehicle locks with a motorized opening drive, as is also shown in
EP 0 589 158 A1.
[0005] Basically, in the above-described motor vehicle lock, a
problem arises in which, depending on the configuration of the
latch and the ratchet, the lifting of the ratchet and thus the
release of the latch are associated with a certain minimum force
and a certain minimum work which are determined essentially by the
friction force between the latch and the ratchet, while the ratchet
is being lifted. In addition to the coefficient of friction, for
the work consumed by friction, the reset force acting on the
ratchet from the latch, and the adjustment path necessary for
lifting the ratchet are decisive.
[0006] While maintaining the described basic concept, a reduction
of the friction force and the work consumed by friction is possible
only to a limited degree without endangering the operating
reliability of the motor vehicle lock. This leads to possible
adverse effects with regard to ease of operation due to high
actuating forces in a mechanically actuated motor vehicle lock.
When the motor vehicle lock is equipped with a motorized opening
drive, the opening drive can be designed accordingly for high
forces or powers. However, this leads to high space requirements
and to high costs.
[0007] One approach to reduce the force necessary for lifting the
ratchet is shown by a known motor vehicle lock described in DE 102
36 282 A1 which shows a ratchet arrangement consisting of two
ratchets. The first ratchet can be caused to engage the latch in
order to keep the latch in the main locked position. The second
ratchet can be caused to engage the first ratchet in order to keep
it in its holding position. The first ratchet is loaded in the
direction of its holding position with a spring, which is
overdimensioned for this purpose.
[0008] The disadvantage in this motor vehicle lock is that the
motion of the ratchets must be matched very exactly to one another
so that the motor vehicle door does not swing back when closing,
caused by overly slow motion of the first ratchet. The matching of
the ratchets to one another makes the structure of the motor
vehicle lock complex and takes place by means of a spring with high
stiffness. This however leads to the actuating forces for lifting
the ratchet being increased. The force which is necessary for
lifting the ratchet is reduced by the reduction of the friction
force, but this reduction is again neutralized at least partially
by the high stiffness of the springs.
[0009] Another approach to reducing the force necessary to lift the
ratchet is shown by the known motor vehicle lock described in EP 0
406 777 B1 corresponds to U.S. Pat. No. 5,092,639, which underlies
this invention. Here, a ratchet arrangement which, like the above
described ratchet, can be caused to engage the latch in order to
keep the latch in the main locked position. The ratchet arrangement
consists of a first lever to which a second lever is coupled with a
swivelling capacity. The engagement necessary to hold the latch
between the ratchet arrangement on one hand, and the latch on the
other, takes place via the second lever. To release the latch, the
first lever is swivelled which leads to swivelling of the second
lever relative to the first lever. At the same time, the second
lever rolls off the latch, to a certain extent, until an unstable
state is formed, and the latch swivels into its open position. The
work consumed by friction can be largely avoided by the swivelling
of the second lever when the latch is released.
[0010] The problem in this motor vehicle lock resides in the fact
that the operating reliability, when the latch is in the main
locked position, cannot be adequately ensured. At high external
accelerations, the second lever can swivel and lead to unwanted
release of the latch. In order to achieve high operating
reliability, high pretensioning of the second lever against the
first lever would be necessary, which can lead to a high force
which is necessary to release the latch.
SUMMARY OF THE INVENTION
[0011] An object of the present invention is to provide a motor
vehicle lock where the force or work necessary to be applied to
release the latch is reduced to a minimum, with high operating
reliability.
[0012] This object is achieved with a motor vehicle lock with a
latch and a ratchet arrangement. The latch is able to swivel around
a swivelling axis, where the latch is able to be moved into an open
position and at least into a main locked position. The ratchet
arrangement is able to move into at least one holding position and
into a release position, and the ratchet arrangement which is in
the holding position keeping the latch in the main locked position.
The ratchet arrangement has ratchet kinematics and an adjustable
blocking element, and by resetting the latch out of the main locked
position in the direction of the open position, the ratchet
kinematics is moved. When the ratchet arrangement is in the holding
position, the blocking element blocks the movement of the ratchet
kinematics, which can be caused by the latch, and blocks the
resetting of the latch.
[0013] First of all, it is important that the resetting of the
latch out of the main locked position in the direction of the open
position causes movement of the ratchet kinematics of the ratchet
arrangement. When the ratchet arrangement is in the at least one
holding position, an adjustable blocking element of the ratchet
arrangement blocks the movement of the ratchet kinematics, which
can be caused by the latch and the resetting of the latch.
[0014] The term "ratchet kinematics" is defined comprehensively
here as any mechanism that is connected between the latch and the
blocking element. When the ratchet kinematics is designed in
accordance with the present invention, the force necessary to
release the latch, specifically the force for moving the blocking
element, can be reduced.
[0015] For a mechanically actuated motor vehicle lock, the
advantage associated with the present invention arises from the
fact that actuating forces necessary for releasing the latch are
low and the lever chains from the ratchet arrangement, especially
from the adjustable blocking element, as far as to an outside
actuating lever or to an inside actuating lever, can be designed to
be comparatively weak. Plastic materials can also be advantageously
used here due to the low actuation forces. This also relates to
connecting elements such as sheathed cables or rods to the outside
door handle or to an inside door handle and the outside door handle
or inside door handle itself.
[0016] There are a number of possibilities for embodying and
developing the present invention.
[0017] With a configuration of the ratchet kinematics as step-down
gearing, the blocking force to be applied by the blocking element
can be reduced. Due to the low blocking force, only a small overlap
between the blocking element and the respective element of the
ratchet kinematics to be blocked is necessary. The work required to
release the latch can be further reduced by the reduction of the
adjustment path of the blocking element.
[0018] The approach, as set forth in the invention, is also
advantageous for a motor vehicle lock with a motorized opening
drive. By reducing the force or work required for release of the
latch, a drive with only small power and, accordingly, with low
actuating currents is needed. Furthermore, with electrical
actuation it is now possible to reduce the actuating times for low
power drives.
[0019] Furthermore, for the aforementioned electrical actuation, it
is also possible to ensure motorized release of the latch both in
normal operation at low seal counterpressures and in emergency
operation at high door counterforces (crash case), since the force
which must be applied to release the latch is reduced based upon
the design of the ratchet kinematics.
[0020] The configuration, as provided by the present invention,
leads to the fact that the latch, with the intermediate lever,
forms a four-bar mechanism with which largely any step-down ratios
can be set. With this simple adjustability of speed reduction,
especially with the variable speed reduction depending on the
position of the latch, the ratchet arrangement can be optimally
matched to any respective application.
[0021] The swivelling connection of the intermediate lever to the
latch obviates the necessity of direct blocking engagement between
the ratchet arrangement and the latch. This yields improved tensile
strength of the motor vehicle lock especially in the direction of
the lengthwise axis of the motor vehicle when high forces act
perpendicularly to the flat side of the latch. The swivelling
connection of the intermediate lever to the latch largely prevents
the latch from sliding past the blocking element. Basically, this
consideration also applies with respect to the tensile strength of
the motor vehicle lock transversely to the lengthwise axis of the
motor vehicle.
[0022] Furthermore, because the intermediate lever is coupled to
the latch with a swivelling capacity, the surface of the latch can
be made mostly in any manner. An especially hard surface of the
latch is not necessary, which leads to the possibility of
configuring the surface of the latch with respect to optimum
tensile strength and at low costs.
[0023] It should be pointed out all embodiments of the present
invention make weight reduction possible, either by using lighter
plastic materials or by designing certain components to be less
"massive" or by using smaller drives.
[0024] The invention is explained below using drawings which show
simply embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] FIG. 1 shows a motor vehicle lock with a latch in the main
locked position and a ratchet arrangement in the holding
position,
[0026] FIG. 2 shows the motor vehicle lock as shown in FIG. 1 with
the latch in the preliminary locked position,
[0027] FIG. 3 shows the motor vehicle lock as shown in FIG. 1 with
the latch in the open position and the ratchet arrangement in the
release position,
[0028] FIG. 4 shows the motor vehicle lock as shown in FIG. 1 with
the latch in the overstrike position (broken line) and
[0029] FIG. 5 schematically shows another motor vehicle lock with
the latch and ratchet arrangement.
DETAILED DESCRIPTION OF THE INVENTION
[0030] FIGS. 1 to 4 show a motor vehicle lock with a latch 2 which
holds the striker 1, and with a ratchet arrangement 3. In
accordance with exemplary embodiments of the invention, the term
motor vehicle lock includes all types of door, hood and hatch locks
associated with motor vehicles. The latch 2 can be swivelled around
a swivelling axis 4 and can be moved into the open position shown
in FIG. 3 and into the main locked position shown in FIG. 1. For
limiting of the swivelling motion of the latch 2 in the locking
process there is furthermore a stationary stop 2a. For side door
locks, the latch 2 can be additionally moved into a preliminary
locked position (shown in FIG. 2). The ratchet arrangement 3 can be
moved into a holding position, shown in FIGS. 1 and 2 and into a
release position, shown in FIG. 3. Referring again to FIG. 1 the
ratchet arrangement 3, which is in the holding position, keeps the
latch 2 in the main locked position and, if provided, in the
preliminary locked position. In doing so, the ratchet arrangement 3
for holding the latch 2 in the main locked position can be moved
into a first holding position and to hold the latch 2 in the
preliminary locked position and can be moved into a second holding
position. But, in accordance with another exemplary embodiment of
the invention, there can also be a single holding position.
[0031] The ratchet arrangement 3 includes ratchet kinematics 5 and
an adjustable blocking element 6. By a coupling between the latch 2
and the ratchet kinematics 5, the resetting of the latch 2 out of
the main locked position shown in FIG. 1, in the direction of the
open position shown in FIG. 3, causes a corresponding movement of
the ratchet kinematics 5. When the ratchet arrangement 3, as shown
in FIG. 1, is in the holding position, the blocking element 6
blocks the movement of the ratchet kinematics 5 which can be caused
by the latch 2, and thus the resetting of the latch 2. The
advantages of this configuration of the ratchet arrangement 3 were
explained above in the Summary of the Invention.
[0032] In one configuration, the ratchet kinematics 5 can be made
as step-down gearing so that the blocking force, which is to be
applied by the blocking element 6 for blocking the latch 2, is
reduced according to the design of the step-down gearing. Here the
concept "step-down gearing" means that the amount of reset force
which acts on the ratchet kinematics 5 by the latch 2 is greater
than the resulting force acting on the blocking element 6 from the
ratchet kinematics 5.
[0033] It was likewise explained above in the Summary of the
Invention that the configuration of the motor vehicle lock with a
motorized opening drive, in conjunction with the described ratchet
arrangement 3, is especially advantageous. Here, the release of the
latch 2 can be triggered by the fact that an opening drive (which
is not further shown) causes movement of the blocking element 6
from the blocking position into the nonblocking position (shown by
the broken line in FIG. 1). In accordance with an exemplary
embodiment of the invention, the opening drive is an electric
motor.
[0034] In the exemplary embodiment shown, the ratchet kinematics 5
has a transmission lever 8 which can be swivelled around a
swivelling axis 7. By resetting the latch 2 out of the main locked
position in the direction of the open position (to the right in
FIG. 1), the transmission lever 8 can be moved to the right. When
the ratchet arrangement 3 is in the holding position, the blocking
element 6 blocks the transmission lever 8 so that resetting of the
latch 2 is blocked.
[0035] Another possible embodiment of the aforementioned principle
that can be implemented with few components is shown schematically
in FIG. 5. The transmission lever 8 can engage the blocking element
6 here as well as the latch 2. FIG. 5 shows the latch 2 in the main
locked position and the ratchet arrangement 3 in the holding
position.
[0036] If, at this point, the blocking element 6 in FIG. 5 is
swivelled to the right, the latch 2 is released. The resetting of
the latch 2 from the main locked position shown in FIG. 5 to the
right, then causes swivelling of the transmission lever 8 to the
left against the pretensioning of springs 8b. The transmission
lever 8 is kept in the deflected position by the guide surface 9
which is located on the latch 2. The blocking element 6 is likewise
kept in the deflected position by another guide surface 10. As the
latch 2 is subsequently moved out of the open position into the
main locked position, the blocking element 6 again engages the
transmission lever 8 by blocking, and thus keeps the latch 2 in the
illustrated main locked position. It is advantageous here that the
transmission lever 8, which is part of the ratchet kinematics 3, is
made as step-down gearing since the swivelling axis 7 of the
transmission lever 8 is not located in the middle, but offset on
the transmission lever 8.
[0037] It should be pointed out that in accordance with the present
invention, the blocking of the transmission lever 8 by the blocking
element 6 is provided preferably in only one direction of the
swivelling of the transmission lever 8. In certain applications,
however it can be advantageous for blocking by the blocking element
to prevent swivelling of the transmission lever 8 in both
directions of the swivelling.
[0038] In the embodiment shown in FIGS. 1 to 4, the transmission
lever 8 is coupled by motion to the latch 2. This means forced
coupling between the transmission lever 8 and the latch 2 which
leads to the movement of the latch 2 resulting in a corresponding
movement of the transmission lever 8.
[0039] In one exemplary configuration in accordance with the
present invention, for the aforementioned coupling of motion, there
is an intermediate lever 11 located between the transmission lever
8 and the latch 2. The intermediate lever 11 is pivotally coupled
to the latch 2 on the one hand, and to the transmission lever 8 on
the other. The coupling point 12 on the latch 2 is eccentric, with
respect to the swivelling axis 4 of the latch 2, and therefore
spaced apart from the swivelling axis 4. Accordingly, the coupling
point 13 is arranged eccentrically on the transmission lever 8 with
respect to the swivelling axis 7 of the transmission lever 8.
[0040] The above described coupling between the latch 2, the
intermediate lever 11 and the transmission lever 8 results in a
four-bar mechanism by which the speed reduction of the ratchet
kinematics 5 which is desired due to a low cost. It is especially
advantageous that the speed reduction of this four-bar mechanism
changes depending on the position of the transmission lever 8.
[0041] The above-described four-bar mechanism is especially
advantageous if the speed reduction is especially high when the
latch 2 is in the main locked position, and if the speed reduction
is accordingly lower when the latch 2 is in the preliminary locked
position. This is advantageous to the extent that the holding
forces which occur when the latch 2 is in the main locked position,
are far higher than when the latch 2 is in the preliminary locked
position. The degree of speed reduction, when the latch 2 is in the
main locked position, is preferably up to eight times greater than
the degree of speed reduction when the latch 2 is in the
preliminary locked position. Overall, the variable speed reduction
of the four-bar mechanism leads to optimum use of the installation
space available in the motor vehicle lock.
[0042] The present invention provides advantages with regard to the
operating reliability of the motor vehicle lock if: 1) when the
latch 2 is in the main locked position or when in the preliminary
locked position, the force acting on the transmission lever 8 from
the latch 2 via the intermediate lever 11 causes torque on the
transmission lever 8 with respect to its swivelling axis 7 and, 2)
if the blocking force of the blocking element 6 opposes this
torque.
[0043] From FIG. 1 it can be recognized that when a force is acting
from the striker 1 on the latch 2 in FIG. 1 to the bottom (for
example, for a tensile force on a closed side door), a
corresponding force is routed from the latch 2 via the intermediate
lever 11 to the transmission lever 8. A line of action 14 of this
force runs through two connecting points 12, 13. Because the line
of action 14 of the force in FIG. 1, runs past the swivelling axis
8 of the transmission lever 8, a torque on the transmission lever 8
in FIG. 1, to the right, is produced. This torque is opposed by the
blocking force of the blocking element 6. FIG. 1 makes it clear
that the speed reduction becomes greater, the closer that the line
14 of action of the force runs to the swivelling axis 7. The two
aforementioned objectives, for the purposes of an optimum
compromise, can be joined to one another by suitable spacing of the
line 14 of action of the force to the swivelling axis 7.
[0044] When the latch 2 is in the main locked position, a tensile
force acts from the striker 1 on the latch 2 (seal
counterpressures), the aforementioned torque on the transmission
lever 8 arises. This leads to the transmission lever 8 being in the
position shown in FIG. 1 and defined by the blocking element 6 in
the blocking position when the latch 2 is in the main locked
position.
[0045] In order to ensure reliable resetting of the latch 2 out of
the main locked position into the open position when the latch 2
released, in one preferred embodiment the transmission lever 8 is
pretensioned and the blocking force of the blocking element 6
opposes the pretensioning of the transmission lever 8. The
pretensioning can also be provided on other components of the
ratchet kinematics 5. With respect to the lever ratios, it is
advantageous if the transmission lever 8 is pretensioned as
described. The direction of this pretensioning is shown in FIGS. 1
to 4 by the arrow 15.
[0046] In order to be able to transmit the aforementioned blocking
force from the blocking element 6 to the transmission lever 8, the
transmission lever 8, in one configuration, has a main catch 16 and
a preliminary catch 16a. As explained above, a preliminary catch
16a can optionally be employed, depending on the application. The
blocking element 6 can be moved to engage the transmission lever 8
by blocking via the main catch 16 and, if present, via the
preliminary catch 16a. This is shown in FIGS. 1 and 2 for the main
locked position and the preliminary locked position of the latch
2.
[0047] The blocking element 6, in one exemplary configuration, can
be swivelled in the manner of a ratchet around the swivelling axis
17. There is also a stop 6a on which the blocking element 6 lies in
the blocking position and against which the pretensioning of a
spring 6b, which acts on the blocking element 6. When the ratchet
arrangement 3 is in the holding position the blocking element 6, as
described above, engages the transmission lever 8 by blocking. This
configuration of the blocking element 8 in the manner of a ratchet
leads to a structurally very simple implementation.
[0048] In one exemplary configuration, the coupling of the
intermediate lever 11 to the latch 2 has a trip-free mechanism.
This makes possible the movement of the latch 2 out of the main
locked position into an overstroke position which is on the other
side of the main locked position, viewed from the open position,
without necessarily entailing the movement of the transmission
lever 8. The overstroke position of the latch 2 is shown in FIG. 4
by the broken line. The overstroke position of the latch 2 is
briefly assumed when, for example, the side door of a motor vehicle
is slammed shut. The transmission lever 8 during this time is
pressed against the stop 8a into its overstroke position so that
the blocking element 6 can engage the blocking position.
[0049] The aforementioned trip-free mechanism is implemented by the
latch 2 having an oblong hole 18 and the intermediate lever 11
having a journal 19 which is located in the oblong hole 18. When
the latch 2 is moved from the main locked position into the
overstroke position, the journal 19 runs in the oblong hole 18, as
is shown in FIG. 4.
[0050] In order to ensure adequate coupling between the latch 2 and
the ratchet kinematics 5, especially for resetting the latch 2 out
of the main locked position into the open position, and the above
described fixing of the transmission lever 8 on the stop 8a for an
overstroke of the latch 2, and furthermore, in order to prevent
uncontrolled running of the journal 19 in the oblong hole 18, the
intermediate lever 11 is pretensioned against the latch 2 such that
the latch 2 can only be moved against the pretensioning into the
overstroke position. This pretensioning can be accomplished by a
pretensioning spring 20, as shown in FIG. 1.
[0051] With the approach as set forth in the present invention,
advantages with respect to protection against theft can be
achieved. One preferred configuration calls for the motor vehicle
lock to have an inlet slot 21 and for the blocking element 6 for
protection against theft to be located in the motor vehicle lock
such that the blocking element 6 cannot be reached from the inlet
slot 21 or can only be reached with difficulty. This means that by
interposing the ratchet kinematics 5 it is now possible to arrange
the blocking element 6 in the motor vehicle lock where it is
protected against unauthorized interventions from the inlet slot
21.
[0052] Furthermore, the approach as claimed in the invention also
offers an especially compact implementation of a locking aid.
According to this configuration there is an auxiliary locking drive
which is not shown and which is coupled to the transmission lever
8. The latch 2 can then be moved into the main locked position by
means of the auxiliary locking drive via the transmission lever 8.
The necessary prerequisite for this is the above explained coupling
of motion between the transmission lever 8 and the latch 2.
* * * * *